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#1
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On the real Baron 58, is there any forward thrust at all with the
props feathered (or set to zero)? I have a slider set to the prop controls and if I set it to zero the plane will still drift forward slowly as I advance the throttles. I'm not clear on exactly what 0% does on the prop control. I notice that it can actually go into negative percentages, but I have no idea what that actually does to the props. Does anyone know? Does 0% actually mean that the prop is feathered? I can see the prop pitch change out the window, so it seems like it does (the blades are almost parallel to the wind with props set to zero). Also, can the props be feathered on a running engine, or is that not a good thing? If you are wondering how I got into this, I feathered the props after simulating a dual engine failure, and forgot to set them back the next time I started up and taxied out. I noticed the aircraft was extremely sluggish until it dawned on me that I had not reset the prop controls. -- Transpose mxsmanic and gmail to reach me by e-mail. |
#2
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![]() Mxsmanic wrote: I'm not clear on exactly what 0% does on the prop control. I notice that it can actually go into negative percentages, but I have no idea what that actually does to the props. Does anyone know? Does 0% actually mean that the prop is feathered? I can see the prop pitch change out the window, so it seems like it does (the blades are almost parallel to the wind with props set to zero). Also, can the props be feathered on a running engine, or is that not a good thing? I can't imagine how/why you would feather the prop with the engine still running. Certainly not something I have or would try. On most all planes pulling the prop level all the way back feathers them. On some older planes there was a feather button but nothing I've flown (DC-3, etc) -Robert |
#3
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You can feather the prop on a PT6 free-turbine engine and
this is a normal training and testing procedure. You do this at idle or very low power settings. On a piston engine, feathering the prop stops rotation, so the engine quits. On a PC game, the electrons stop flowing? "Robert M. Gary" wrote in message ps.com... | | Mxsmanic wrote: | I'm not clear on exactly what 0% does on the prop control. I notice | that it can actually go into negative percentages, but I have no idea | what that actually does to the props. Does anyone know? Does 0% | actually mean that the prop is feathered? I can see the prop pitch | change out the window, so it seems like it does (the blades are almost | parallel to the wind with props set to zero). | | Also, can the props be feathered on a running engine, or is that not a | good thing? | | I can't imagine how/why you would feather the prop with the engine | still running. Certainly not something I have or would try. On most all | planes pulling the prop level all the way back feathers them. On some | older planes there was a feather button but nothing I've flown (DC-3, | etc) | | -Robert | |
#4
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![]() Jim Macklin wrote: You can feather the prop on a PT6 free-turbine engine and this is a normal training and testing procedure. You do this at idle or very low power settings. On a piston engine, feathering the prop stops rotation, so the engine quits. On a PC game, the electrons stop flowing? I wondered about that. In a turboprop the engine starts with the blades feathered. However, I don't have the experience to comment on them. -Robert |
#5
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![]() "Robert M. Gary" wrote in message oups.com... Jim Macklin wrote: You can feather the prop on a PT6 free-turbine engine and this is a normal training and testing procedure. You do this at idle or very low power settings. On a piston engine, feathering the prop stops rotation, so the engine quits. On a PC game, the electrons stop flowing? I wondered about that. In a turboprop the engine starts with the blades feathered. However, I don't have the experience to comment on them. -Robert As Jim said the PW PT6 engine has no physical connection between the power section and the drive section. When you turn the prop by hand you are not turning the engine. Some actually have a prop brake so you can stop the prop with the engine running to be able to run the accessories (AC and generator). The Garret turbine engines are direct drive, they have a driveshaft between the engine and drive section. When you turn the you are turning the engine. These engines will not start in the feathered position. Allen |
#6
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Allen writes:
As Jim said the PW PT6 engine has no physical connection between the power section and the drive section. How does power get from one to the other? -- Transpose mxsmanic and gmail to reach me by e-mail. |
#7
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The PT6 and some other turboprop engines are "free turbines"
with a gas generator section that sends gas to a separate turbine/gear box assembly. Until the engine develops oil pressure, the prop is feathered. Other turbine engines, the Garrett TPE331 being the most common example, has a solid shaft that drives the prop from the gas section. These engines are shutdown after locking the prop blades at near zero pitch, otherwise the loads required to start the engine would strain the starter motor. In-flight feather and restarting requires that the prop be manually unfeathered to restart the engine. The complications of the TPE331 over the PT6 are a prime reason the PT6 is the preferred engine by most pilots. The low cost and slightly high fuel specs make the TPE331 make it popular with bookkeepers. http://home.swipnet.se/~w-65189/turb...ne_engines.htm http://www.pwc.ca/en/3_0/3_0_2/3_0_2_1_1.asp http://www.aircraftenginedesign.com/TPE331pics.html "Robert M. Gary" wrote in message oups.com... | | Jim Macklin wrote: | You can feather the prop on a PT6 free-turbine engine and | this is a normal training and testing procedure. You do | this at idle or very low power settings. On a piston | engine, feathering the prop stops rotation, so the engine | quits. | | On a PC game, the electrons stop flowing? | | I wondered about that. In a turboprop the engine starts with the blades | feathered. However, I don't have the experience to comment on them. | | -Robert | |
#8
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![]() Jim Macklin wrote: You can feather the prop on a PT6 free-turbine engine and this is a normal training and testing procedure. You do this at idle or very low power settings. On a piston engine, feathering the prop stops rotation, so the engine quits. On a PC game, the electrons stop flowing? BTW: My kids got me MSFS X for my B-day. I honestly haven't had the time to install it. However, my son and I played JetFighter IV yesterday. Much more fun than MSFS. Not much of a simulator but its fun learning how to use the different types of air-to-air missles and air-to-ground bombs/missles/etc. The tactical avionics seems pretty realistic although I don't have much comparison. The "fire and forget" missles are much easier than the dumb bombs,. -Robert |
#9
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Robert,
I honestly haven't had the time to install it. Well, let's hope you at least have the 15 Gig (!) of free HD space it requires. -- Thomas Borchert (EDDH) |
#10
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![]() Thomas Borchert wrote: Robert, I honestly haven't had the time to install it. Well, let's hope you at least have the 15 Gig (!) of free HD space it requires. So what? Disk space is basicly free nowadays. -Robert |
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